1. Field of the Invention
The present invention relates in general to local area networks, and specifically to in-band link signaling with programmable Q-ordered sets.
2. Background Art
Ethernet protocol is a popular technology used to implement Local Area Networks (LANs), and was originally developed in the late 1970s. In 1985, Ethernet was adopted by the Standards Board of the Institute of Electrical and Electronics Engineers Standards Association (IEEE-SA) as IEEE Std 802.3® The Ethernet protocol provides a process whereby a node can communicate with its link partner(s) to manage their shared portions of the LAN. Typically, this is accomplished by messages communicated between nodes when their transceivers are in idle mode. For example, a node experiencing a fault can communicate this condition to its link partner(s) (i.e., local fault). A node can also detect a fault condition in a link partner (i.e., remote fault). Additionally, messages can be used to report the specific message handling capabilities of a link partner, the status of synchronization between link partners, and the like.
The IEEE-SA has approved an amendment for “Media Access Control (MAC) Parameters, Physical Layers, and Management Parameters for 10 Gb/s Operation” to IEEE Std 802.3. The amended standard is designated IEEE Std 802.3ae™. In idle mode, IEEE Std 802.3ae uses ordered sets of code groups: (1) to verify that code group reception of each lane is synchronized, (2) to check alignment of each lane relative to the others, (3) to provide for clock rate compensation, (4) to relay local fault signals, and (5) to relay remote fault signals. What is needed is a mechanism that extends the ability, beyond the specific features provided for by IEEE Std 802.3ae, of nodes to communicate with each other when their transceivers are in idle mode.